Improvement in sewing-machines



, 4 Sheets-Sheet I. 4 A. F. JOHNSON.

Sewing Machine. 1- Patented ApriH2i, 1864.

w k i w 4 Sheets-Sheet 2. A. F. JOHNSON.

Patented April 12, 1864.

Sewing Machine.

M/ZW: Z4 JW N. PETERS. Phukn-Llllvogmplvcr, Nnshmglnn. n c.

4 Sheets-Sheet 3. A. F. JOHNSON.

Sewing Machine. No. 42,292. 2 Patented April 12, 1354.

2 4 Sheets-Sheet 4 A. F. JOHNSON;

Sewing Machine.

Patented Aprill 12, 186.4.

UNITE A. I JOHNSON, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN SEWING-MACHINES.

50 all whom it may concern:

Be it known that I, A. F. JoHNsoN, ot'Boston, in the county of Suffolk and State of Mas sachusetts, have invented Certain new and useful Improvements in Sewing-lllachines; and I do hereby declare that the following description, taken in connection with the accompany" ing plates of drawings, forms a full and exact specification ot' the sauie,'whereiu I have set forth the nature and principles of my said improvements, whereby myinvention may be dis-- tinguished from all others of a similar class, together with such parts as I claim and desire to have secured to me by Letters Patent.

The present invention relates almost entirely to improvements in the method of producing a wax-thread seam for the uniting of heavy fabrics,like leather, such as are used for boots or shoes, harnesses, carriages, &c., although it will apply essentially to the sewing of other materials as well when other threads are to be used.

Previous to entering into a detailed description of my invention it maybe well to show what, in the course of many experiments and investigations,Ihavefound to be theditliculties to be overcome and the essential requisites to be embodied in a sewing-machine for producing this class of goods, as 'it'will tend to point out more clearly the salient points of my invention and wherein they differ from what has before been done.

The only wax-thread sewing machinery heretofore used that has approximated to the accomplishmentof practical results'has been that by which asingle-thread or tam bour stitch has been produced, it having been found impossible to form a seam by a double-thread or look stitch in such heavy goods with a waxed or tarred thread, although it is evident and has rial,likeleather, and giving theloop to the shuttle, and again while drawing through the eye of the needle to tighten up the slack loop through which the shuttle has just passed. This chafing of a wax-thread also'would fill the eye of the needle with gum and lint and render it inoperative. Again, as an eyepointed needle is necessarily grooved longitudinally in order to permit the thread and needle to pass together through the goods, a waxed or tarred thread would stick in this groove and prevent the formation of a loop for the passage of the shuttle. Furthermore, an eye-pointed needle to pass through very thick go0ds-such, for instance, as a thorough-brace used in carriageswould have to be so long as to be inoperative, because it is necessary in using a wax-thread to give a loop sufliciently large to pass around and allow the free passage of the shuttle, on account of the great friction that would otherwise be produced by the thread upon the same and the impossibility of drawing the loop down through the goods by the passage simply of the shuttle, as is the case in the use of a dry thread. In the use of an eye-pointed needle also, as it carries down with it a double thread or loop through the fabric, the loop and needle are liable to be wedged in the same, and this would be especially the case in sewing leather goods with a waxed thread.

It has been attempted to obviate the difliculties experienced in the use of an eyepointed needle byemploying an awl for puncturing the leather, in combination with a hooked needle, which pulled the thread down through the same; but this has produced only a single-thread stitch. Moreover, the tighteningot'the stitch was necessarily performed by the hooked needle itself, and during the most ot'the'operation the thread was unavoidably under full tension. Now, to draw a double waxed thread under great tension through such hard and heavy materials by means of the hooked needle will occasion such great friction as to prevent satisfactory results from being attained in sewing unyielding materials, such as leather. Inthese machines, in which anawl and hooked needle are used, the tightening of the stitch is necessarily performed while the needle is in the goods, and the hooked needle has to draw the waxed thread double orin a loop form through the same. This causes so much friction as to render it nearly or quite impossible to use a shuttle under such circumstances, as the shut tle could hardly pass through a loop undersuch great strain while pulling the thread down through the goods, especially ifthey were nonelastic. After many practical tests, then. it became desirable that the machinery for producing a double or lock stitch in leather or other similar-s fabrics that are to be united with a waxed thread should be subject to the following conditions: First,asubstituteorsubstitutes for an eye-pointed needle which would be free from its defects, as hereinabove enumerated, for puncturing the hole through the fabric and carrying the thread through the same; second, that a shuttle or other device for interlocking one thread with another should be so combined with the other devices as to be free to pass through the loop of the needle-thread without strain or friction; third, the tightening of the stitch should be performed when the needle or other instrument is not in the goods with the waxed thread, and that while the thread is being passed down through the fabric it should be slack, or without being subject to any tension during the whole timeitis being so passed.

By my improvements in sewlng machinery I have successfully accomplished the above named desiderata. In lieu of an eye-pointed needle,I employ a puncturing-awl and an openeyed hooked needle, and with these is combined a shuttle for causing the formation of a lockstitch. To obviate the necessity of allowing the needle to remain inthe fabric while the stitch is being tightened, which, as hereinbefore shown, is fatal to practical sewing with a waxed thread, an arrangement of devices or take-up is employed which operates entirely independent of the movement of the needle, and in such a manner that while the thread is being conveyed through the fabric it shall be" slack and subject to no tension.

In the accompanying plates of drawings my improvements in sewing-machines are represented.

In Plate 1, Figure l is a side view of my improved sewing-machine. Fig. 2 is atransverse vertical section taken through the planeofthe line A B, Fig. 7, Plate 2. Fig. 3 1s a transverse vertical section taken through the plane of the line 0 D, Fig. 7, Plate 2. Figs. 4., 5, and t) are detail views, which will be hereinafter more particularly referred to. In Plate 2, Fig. 6 isacentral longitudinal vertical section. Fig. 7 is a plan or top view and Figs. 8 and 9 detail views of the shuttle of the machine.

a a in the accompanying drawings represent the frame-work of the machine; I) b, the driving-wheel turning upon a horizontal shaft, 0, of the frame-work a. Attached to thedrivingwheel I), and revolving with it, is a gear-wheel, d, engaging with a similar gear, 6, on a horizontal shaft,f, having bearings at g in the frame-work a, and in a projection, h, of the same.

Near one end of the shaftf, and forming a part of the same, is' a crank, 2', attached to which is a vertical shaft,j, the upper end of the same being secured to the arm or crank It on one end of a horizontal shaft, 1. The shaft 1 turns in hearings on m of the standard a.

At one end of the horizontal shaft l is a crank-disk, 0, to one side of which the upper end of a short connecting-rod, p, is secured, the other end of the same being fastened to the vertical awl-bar q, moving in suitable bearings of the vertical arm 1*,the awl 8 being arranged in a vertical position at the lower end of the said bar q in a manner which will be hereinafter described.

The above arrangement of devices is for operating and moving the awl up and down in a vertical plane for puncturing the fabric to be sewed, the operation of which, in connection with the other parts of the machine, will be hereinafter explained.

tt is the shuttle, moving in a horizontal groove or way, u. of the platform to, and below its upper surface. At each end of the shuttle t t, and abutting against the same, are two projecting arms, e '0, of the horizontal plate or, that is guided by a groove, y, in the platform to. To the under side of the plate as the upper end of a curved arm, 2, is secured, the other end, by means ofa connecting-rod, a, being attached to and receiving motion from the outer end, I), of a crank or arm, 0, on the main shaftf, before referred to. The devices thus arranged and connected with the driving-wheel serve to impart at the proper times the desired reciprocating movement to the shuttle, to be presently specified.

Placed longitudinally within and in the center of the shuttle t t is a'spool, d, turning on a shalt, e. 'Wound on this spool is the thread or other material used, the thread passing out of the said shuttle through the openingf in the periphery thereof, (see Fig. 7, Plate 2,) and then laid along the groove g of the same in its proper position.

it is a crank attached to the crank-arm 0, before referred to, and to a connecting-rod, i, the other end being secured to the lower portion of the vertical needle shaftj. This needle-shaft moves in bearings it, and within the same is another shaft, 1, in the upper end of which,and eccentric therewith, (see Fig. 9,) the needle m is inserted.

In the periphery of the shaft Z is a vertical slot, a, straight to the point 0, but then passing spirally around the said shaft for about one-third ofits periphery, (see Fig. 9,) in which groove bears a stutbp, ot' the bearings It" It.

By the above arrangement, as the drivingshal't revolves an up-and-down movement is given to the needle, and its shattis also caused to partially rotate, for purposes and in a manner to be hereinafter set forth.

(1 is aspool, around which is wound the thread 7", and which turns on a spindle, s, fastened in the standard a. This thread is then passed from the said spool to and around the guidingpulley a of thestandard t; thence through the openings v o of the swivel-box a, turning on a shaft, 02, and around a pulley, w, within said box a, the shaft :0 being a prolongation of the vibrating arm y, secured rigidly to the crank 0, before referred to, which arm, by its reciprocating motion, in connection with the box v and pulley iv, slackens and tightens the threads in formingthe stitch in a peculiar and novel manner to be hereinafter explained. Thence from the pulley w it is passed to and through the opening or eye 2 of the curved thread-carriera, with bearings at b b. This eye 2 is placed a little below the horizontal .plane of the hook c of the needle at when .at

its highest position, (see Fig. 1,) and s also made to partially revolve in a horizontal plane around the needle by means of the stud d of the awl-bar q, traveling in the curved slot 0 in said threadcarrier c.

Having thus in detail specified the arrangements of the various parts comprising the machine and their connection with the drivingwheel, I will now proceed to explain the general manner in which the same operate to form the stitch in the fabric to he sewed.

The fabric to be sewed having been placed in its proper position on the platform and the two threads arranged in the manner specified, thedriving-wheelthen being turned, the awl S, by means of the connecting devices before described, descends, puncturing thefabric, and at the same time feeding it along by an arrangement ofdevices to be presently explained, till the aperture thus made is in the proper position for the needle to pass through the same inits upward movement. While the awl is thus descending the needle also descends by means of the connecting devices beforedescribed, and passes down through the aperture made in the fabric by the previous descent of the awl, carrying with it the thread 1", which had been first placed around and within its book 0, by means of the thread-carrier a, arranged and operating as specified. This needle continues to descend until it has passed entirely through the fabric, when, by means of the groove a and the stud p, the needle is made to revolve, making about a third of a revolution, for the purpose of bringing the loop formed by its book and carried through the fabric in the path of the shuttle. During the downward movements of both the awl and the needle the shuttle it travels in its guidingway across the machine to the position indicated by red lines in Fig. 7, Plate 2, when, as the needle and awl commence to ascend, it moves forward, passing through the loop of the thread left in its path by the hooked needle. This movement of the shuttle continues until the awl and needle have both reached their uppermost position, the needle having passed upward through the aperture just punctured by the awl. The needle and awl then again descend and the movements above described take place as before; but in order to tighten the loop carried through the fabric by the hooked needle and interlock with it the shuttle'thread, I have provided the arrangement of devices as hereinbefore specified, consisting of the vibrating arm 3 swivel-box o, and pulley w. The operation of these, in connection with the movements of the needle and awl,

is as follows: As they are descending the vibrating arm moves from its upper position (in dicated by black lines in Fig. 2) to the position indicated by red lines in said figure, drawing the thread from the spool and feeding it along in a slack condition to the needle; but as they ascend the arm travels back to its original position, and so on until the machine is stopped. By this forward and backward movement of the arm it will be observed that during the whole time occupied by the needle in its descent the arm is drawing the thread from the spool and feeding it to the needle, thereby keeping the thread always slack while being pulled through the fabric; but that as the needle ascends the arm then, by traveling back to its starting-point, draws up and. tightens the loop in the fabric, the importance of both of which in the sewing of leather fabrics-like boots, shoes, harnesses, &c.-have been here inbefore particularly set forth.

To obviate the liability of the thread being detached from the pulley of the vibrating arm as it moves back and forth, I have inclosed the same within the box a, which box swivels on its shaft and thus prevents friction of the thread in the apertures c '0.

g is a rod hung on a pivot, h, of the awlbar. In the lower end of the rod g is the awl s, before referred to.

l is a spring whichbears against the rod 9, and as the awl descends throws it away from the line of travel of the needle, its lenth of motion being regulated by the set-screws m. a is another adjustable screw, placed in a lower plane than the screw m, and which bears against the inclined surface 0 of the rod g"as it passes down by the same.. These two screws are so adjusted with regard to each other that while the first will allow of the swinging movement of the awl-arm g,as described,the other will cause said arm to be gradually brought back to its original position, thereby at the same time feeding along the fabric to the hooked needle, as is evident without further description. This swinging movement of the awl takes place as it descends, and it is obvious that the awl can be so operated upon by the proper adjustment of the set-screws as to vary the length of the stitch as may be de-c sired.

It is not necessary that the under thread should be carried by a shuttle and so passed through the loop of the upper thread; but the same result may be accomplished by passing the loop of the upper thread over or around the under thread; but I have preferred the former motle'for present-purposes. The same result may be arrived at by using the hook or crochet-needle as the piercing-instrument and feeding the fabric by that or by other feeding devices; but the method I have described is better for most. if not for all, purposes, especially when the fabric is stifl' and unyielding.

Having thus described my improvements, what I claim as my invention, and desire to have secured to me by Letters Patent, is-

1. Forming a seam or seriesot' stitches by pulling in contradistinction to pushinga thread through the fabric by means of a hook-needle and passing another thread through the loop of theformcr by means of a shuttle orits equivlent, when used in combination with the feeding mechanism of a sewing-machine.

2. In combination with a sewing-mechanism operating as described, keeping the thread slack or free from tension while being drawn through the fabric by the hook-needle, substantially as described, so as to prevent the great friction and strain that would otherwise occur, as set forth.

3. Such an arrangement of devices or takeup for tightening the'stitch and supplying the needle as will operate independently of the hook-needle, or ofits motion, so as to avoid the necessity of drawing the thread through the fabric to tighten the stitch by means of the hook-needle itself, as set forth.

4. Giving the needle both an eccentric and rotary movement for the purposes specified.

5. The combination of an awl or other device t'or puncturing the fabric, an open-eyed hook-needle for seizing and pulling the thread through the fabric, and a shuttle or other device for interlocking one thread with another, the Whole operating together substantially as described.

6 The combination of an aWl or perforating device, open-eyed or hook needle, shuttle, or

awl bar, in combination with set-screws mn,

or other-equivalent adjustable devices, respectively, for regulating the length of stitch and for feeding the fabric to the needle.

A. F. JOHNSON.

Witnesses:

JOSEPH GAVE'IT, ALBERT W. BROWN.- 

